OAI/Algebra/Finitistic/Dimension/PDLowerBound.lean
4 declarations, 0 contain sorry, 0 declared as axioms
- theorem
OAI.LittleFinitistic.PDTensor.tor_zero_of_pdLTline 14Source documentation
Any right module detects a lower bound through nonzero Tor; it need not be flat, finite-dimensional, or annihilated by the radical.
theorem tor_zero_of_pdLT (n : ℕ) (h : HasProjectiveDimensionLT M.cat n) : IsZero (Tor (k := k) U M.cat n) := by …Mentions: OAI.LittleFinitistic.PDTensor.Tor
- theorem
OAI.LittleFinitistic.PDTensor.le_projectiveDimension_of_nonzero_Torline 27 - theorem
OAI.LittleFinitistic.PDTensor.lower_bound_of_nonzero_Torline 32 - theorem
OAI.LittleFinitistic.PDTensor.projectiveDimension_lt_top_of_bounded_residueTorline 37Source documentation
Bounded radical-quotient Tor gives finite numerical projective dimension.
theorem projectiveDimension_lt_top_of_bounded_residueTor (h : ∃ b : ℕ, ∀ n, b < n → IsZero (Tor (k := k) (Residue (A := A)) M.cat n)) : …Mentions: OAI.LittleFinitistic.PDTensor.Tor, OAI.LittleFinitistic.PDTensor.Residue